A ball A moving with a velocity 5 m/s collides elastically with another identical ball at rest such that the velocity of A makes an angle of `30^(@)` with the line joining the centres of the balls. Then consider following statements :
(A) Balls A an B move at right angles after collision
(B) kinetic energy is conserved
(C) speed of A after collision is (5/2) m/s
(D) speed of B after collision is (`5sqrt(3)//2`) m/s
Select correct alternative :-

Options

A. Only (A) and (B)
B. Only (A), (B) and (C)
C. Only (A), (B) and (D)
D. All are correct

Answer

A